Automatic connect and disconnect apparatus for hydraulic testing tools



July 6, 1965 I G. L. LOOMIS 3,193,015

AUTOMATIC CONNECT AND DISCONNECT APPARATUS FOR HYDRAULIC TESTING TOOLS Filed Aug. 20, 1962 2 Sheets-Sheet 1 I NJ 7 (a I /fa i l Q I 3 I I 4 M L.

fit/WV z. ZZZ 3% rraeME/s y 6, 1965 G. L. LOOMIS 3,193,015

AUTOMATIC CONNECT AND DISCONN APPARATUS FOR HYDRAULIC TESTING LS Filed Aug. 20, 1962 2 sheets sheet 2 A 44/ W/A 52 74 INVENTOR.

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United States Patent AUTOMATIC CUNNECT AND DISCONNECT APPARATUS FOR HYDRAULIC TESTING TOOLS Glenn L. Loomis, Pasadena, Tex; Jean Doyle Loomis, independent executrix of said Glenn L. Loomis, deceased, assignor to Jean Doyle Loomis Filed Aug. 20, 1962, Ser. No. 217,791 2 Claims. (Cl. 16667) The present invention relates to a connect and discon nect apparatus for tools insertable into well tubing or the like, and, more particularly, to an automatic connect and disconnect apparatus for use with testing tools used in testing stands of well tubing as the well tubing is installed in oil and gas wells or the like.

In my prior United States Patent No. 2,731,827, issued January 24, 1956, a tool for testing well tubing is disclosed as well as a procedure for installing the well tubing in oil and gas wells. The procedure disclosed in the aforementioned patent, which is generally used today for assembling and installing well tubing in oil and gas wells, includes joining together a multiplicity of tubing sections and placing these sections or stands, as they are generally referred to, in a generally upright position in a rack adjacent the derrick. This is done in order to save time during the actual tubing installation, as the stands may be joined together more rapidly than is the case when one tubing section is installed at a time. A well derrick is usually provided with a platform or monkeyboard near the top thereof about fifty to seventy-five feet or higher above the derrick floor on which a crew member is stationed. The crew member, at this position, latches the conventional elevator device onto the upper end .of an upright stand and the stand is then hoisted into position for attachment of its other end to a previously-run stand.

The connections between two stands are usually threaded connections or threaded collar joints although they may be welded to one another. Each connection, as well as the length of the stand, must be tested for leaks at least at pressures which the well tubing will encounter when lowered within the well. In the hydrostatic testing of the stand and its threaded connections to another stand, a test tool of sufiicient length is utilized to encompass the entire stand, and usually such test tool is left suspended within the tubing string after the test, as shown in the prior United States Patent No. 2,610,691, issued September 16, 1952 to Berry, or United States Patent No. 2,652,-

.717, issued September 22, 1953 to Bush and Collet, and

then the string is lowered down in the well bore prior to the attachment of another stand. Heretofore, a wire line grapple was lowered through the newly-attached stand to engage the testing tool so that the same may be pulled upwardly into the newly-attached stand until its upper packer is near the top of the same. With the test tool in this position, hydraulic pressure is applied, and the testing operation is performed, this operation being performed above the floor level of the derrick and above the usual slip-holding devices which engage the previouslyrun stand.

It is desirable to test a newly-attached stand and its joint above the derrick floor level from a safety standpoint because, if there is a failure of the tubing or a failure of the threaded coupling, the entire tubing string will not be dropped into the well bore but is retained by the slip-holding device. Also, testing above the floor of the derrick and above the slip-holding device eliminates an expensive fishing job caused by the tubing string being dropped and also eliminates the danger of rapid agitation of the weighting fluid and the resultant blowout of the well.

Ancillary to the above, it is more efficient to test a stand and its threaded joints above the derrick floor as the testing crew member can make a visual test as Well as a test determined by the drop of pressure on a pressure gauge. Oftentimes, small leaks which are detrimental in high pressure gas wells are difiicult to locate by means of a pressure drop and can only be located by use of visual means.

In addition to the above, it is a further advantage to test well tubing above the holding slips, as wells are usually loaded with a heavy viscous mud for creating sufficient hydrostatic head to overcome well pressure at the producing level. If testing below the well surface, this heavy mud oftentimes mixes with testing fluid and prevents a true test, insomuch as the nature and viscosity of the mud will stop a leak which would otherwise appear with clear water or other fluids.

Although testing has been accomplished heretofore above the floor of the derrick, there have been many difficulties encountered in performance of the operation. One of the principle difiiculties arises from the fact that the top of the stand to be tested, after it has been hoisted into position and threaded onto a previously-installed stand, is above and out of reach of the man on the monkeyboard even though the monkeyboard may be positioned upwardly in the derrick fifty feet or more above the derrick floor. In order that the wire line grapple may be disconnected from the test tool after it has been raised in the stand to be tested and the pressure lines attached to the top of the test tools, it is necessary for the crew man to unbuckle his safety belt and climb up the derrick and swing out to disconnect the grapple and connect the pressure lines.

Oftentimes, it is necessary to place a second derrick man on the monkeyboard to perform this operation and, at best, this is a very hazardous operation as it is done a considerable distance above the monkeyboard fioor. During nighttime and inclement weather, it is also impossible to accomplish, and oftentimes results in a delay in completion of a well.

Another difficulty in the prior procedure of testing wells is due to the fact that the hoisting sheaves and hooks used on modern well rigs are massive and require considerable space in the derrick. Heretofore, a weight such as a rigid steel bar several feet long has been attached to the top of the wire line grapple in order to counterbalance the weight of the test tool hoisting cable which runs over a pulley attached near the top of the der rick. The grapple with the weight bar was inserted by the derrick man in the tubing stand before the elevator was latched, but when the stand was attached to the tubing string, the derrick man had to unlatch the elevator in order that the grapple and bar could be withdrawn to be disconnected. In other words, the elevator was unlatched and pulled to one side out of the way so that the weight bar and the grapple could be withdrawn and the grapple disconnected. After the test is completed, the elevator had to be relatched to thestand; and, as will now be evident, such operation consumed additional time and was a hazard to the derrick man working on the monkeyboard.

An important object of the present invention is to provide an automatic connect and disconnect apparatus for use with tools insertable into the well, the apparatus obviating dangers to personnel as well as reducing the time for completion of the well.

Another important object of the present invention is to provide an automatic connect and disconnect apparatus for tools insertable in the well tubing and to which fluid under pressure is flowed, the apparatus providing means for automatically connecting the fiuid pressure supply to the tool. Ancillary to the immediately preceding object,

it is a further object to provide such apparatus for use with testing tools.

Still another object of the present invention is to provide an automatic connect'and disconnect apparatus which may be operated .by remote control in the will of the derrick man stationed on the monkey board or at the derrick floor, the apparatus providing means for remote- 1y disconnecting the grappling hooks from a tool within a stand of well tubing, and remote controlling operation of a tool in the well tubing. 7

A still further object of the present invention is to provide an automatic connect and disconnect apparatus for test tools for oil and gas wells, the apparatus being generally supported on the end of stand of well pipe and capable of being connected to a test tool, the stand being rotatable relative the apparatus and tool connected there- Throughout the specification, the invention will be described in connection with its use with an oil or gas well testing tool, .but, of course, could be used on any tool used Within well tubing for various other treatments of the same such as a tubing leak repair tool, a cement tool,

a blowout tool, or the like, a

The above objects, as'Well .as other objects and advantages of the present invention, will appear more fully in the following specification, claims and drawings in which:

FIGURE 1 is aschematic, perspective view showing the upper portion of a derrick and illustrating the present invention attached to the upper end of a stand of well tubing;

FIGURE 2 is an enlarged, fragmentary, perspective view of the jointed weight bars or flexible weight;

FIGURE 3 is an enlarged, fragmentary, vertical, sec-1 back to'a position where it is longitudinally aligned with wthe tubing string, and in order to do this, the elevator per end is above the usual holding slips.

20 must be hoisted by the traveling block18 and the upper end of the stand will then be out of reach of the derrick man; However, the lower end of the stand is in position adjacent the upper end' of a previously-run stand which has been lowered into the well to a position where its up- I With the stand S. in the: axially aligned position with the well tubing "string, the stand S is then threaded onto the previouslyrun stand and, after the coupling operation is completed, the usual testing of the threaded joint, as well as the length of the stand,is accomplished above the holding slips. If there is any failure either in the threaded joint or coupling or in the length of the stand, the previously- 7 run stands ofthe tubing string will not fall down into the well. Once the test has been made, and it has been found that the coupling joint as well as the length of stand is satisfactory, the well tubing string is lowered until the last tested stand has its upper end'immediately above the holding slips. p V

Referring now to FIGURE 3, which discloses a vertical section through a portion of the automatic connect and disconnect apparatus generally designated at 24, it will be noted that such apparatus includes a body portion 26 which is provided with a downwardly-facing annular collar 28' threaded exteriorly as indicated at 30. The body portion 26 is generally of greater diameter than the diameter of the stand S and is provided with a bore 32 extending therethr'ough. Carried within the collar 30 is a thrust bearing assembly 34 having a ring member 36 for engaging the upper'end of the stand 8' at 38.

Threaded onto the threads 30 of collar 28, is an annular guide sleeve 40 having an inside diameter greater than the outside diameter of the stand 8, the sleeve 40 having its lower end tapered as indicated at 42, and, thus, provid-- ing a guide when the apparatus 24 is placed over the endof a stand. 7 V

7 An upwardly-extending annular collar 44 is provided on the body portion 26, the collar 44"being exteriorly threaded as indicated at 46, and receiving the lower end Referring now to the drawings wherein like character 1 and reference numerals representlike or similar parts, the

numerallt) generally represents a typical derrick used in ing bloc The hoisting sheave 18 is massive in size and supports the usual elevator generally designated at 20, the

elevator being capable of detachably clamping to the end of a stand S of Well tubing for elevating the same of a cylinder 48 The cylinder 48 is provided witha bore '50 in its'upper end or head 51 through which extends a hollow piston 52 having a piston head 54. The piston head 54is provided with suitable piston rings 56 for engaging the interior walls of the cylinder .48, while O-rings 55 are provided in the cylinder head 51 for engaging the exterior walls of the hollow piston. A lateral port 58 I in the wall of the cylinder 48 has connected thereto a from a rack (not shown) and positioning the same in axial alignment with a previously-run stand of well tubing so that it may be threaded or suitably secured to the pre viously-run stand of well tubing.

A platform 22 is provided on the derrick at an elevation above the -floor of the derrick, the platform being provided for the derrick man who connects and disconnects the elevator 20 from a'stand S. The platform 22 which is known as a monkeyboard is usually fifty feet or more above ground level or the floor of the derrick.-

In any event, the platform 22 is supported on the derrick to a stand of a previously-run tubing string, the derrick" man swings the elevator 20 over and latches the same on a racked stand. Then the derrick man swings. the stand The maximum exterior diameter of the cage 72 is less conduit 60 through which a fluid under pressure can be 'fiowed from a suitable source of fluid pressure 61 to the area beneath the piston head 54 so as to extend the piston downwardly withinthe chamber of the cylinder 58.- A'portion of the hollow piston .52 extends out of the cylinder 48 and is interiorly threaded as indicated at 62. A ring nut 64 having-a center bore 66 is threaded into the end of the piston 52"and a spring 68 interposed between the head ofnut 64 and the cylinder 48 normally causes the piston to assume a retracted position.

The lower end of grappling means generally indicated at 70 extends into the hollow piston 52 as best shown in FIGURE 3. The grappling means 70 includes a cage 'member 72 having ring 74 at its lower end from which extend oppositely-disposed side members 76 and 78 respectively. Supported within the cage member by means 'of a pivot pin 80 are a pair of grappling hooks 82 which 'are spring-urged to a grappling position by means of leaf, springs 84. j The leaf springs 84 fit into suitable slots in the upper ends of the grappling hooks 82, the other ends of thesprings 84 being fixedly secured bymeans of screws 86 to thestemportion 88 of the grappling means.

than the diameters of the bore 32 in the body portion 26 as the grappling means 70 must be capable of being lowered vertically through the body portion 26 down into the stand S.

The ring nut 64 is provided on its stem 65 with a camming surface 67. When the piston 52 is extended, the camming surf-ace 67 of ring nut 64 engages the leaf springs 84 to compress the same and cause the hooks 82 to move to the dotted line release position 83 as shown in FIGURE 3.

The stem portion 88 as shown in FIGURE 1, is provided with a hook 90 at its upper end to which is connected a plurality of bars 92. Each bar 92 is jointed to another bar 92 so that it can be pivoted with respect thereto. As shown in FIGURE 2, the bars 92 may be connected by means of links 94. The uppermost bar 92 is connected to a hoisting cable 96 which extends over a pulley or sheave 100 supported from the frame structure 14 on the upper end of the derrick 10. The hoisting cable 96 extends downwardly to a suitable hoisting drum 102 carried either on the floor of the derrick as schematically shown in FIGURE 1, or on the platform 22 if so desired. As will now be apparent, the short sections of bars 92 connected to each other provide a flexible weight which can be deviated from the axis of the stand so that it can pass by the hoisting sheave or traveling block 18 when in the position shown in FIGURE 1. The bars 92 are usually on the order of seven feet in length and have a combined weight to substantially counterbalance the weight of the hoisting cable 96 when the grappling means 70 is in its uppermost position. In other words, the counter weight made up by the short bars 92 is necessary in order to counterbalance the weight of the length of hoisting cable 96 between the sheave 100 and the hoisting drum 102, otherwise, the grappling means 70 might be pulled completely out of the stand and over top of the sheave 100. The elongated bars 92 are substantially circular in cross section and have a maximum diameter less than the minimum diameter of the bore 32 in body portion 26, as well as the diameter of the stand S as the bars pass through the bore 32 into the stand S when it is desired to grapple onto a tool supported in a previously-run stand.

As shown in FIGURE 3, the grappling means 70 is illustrated hooked onto the end of a desired tool generally indicated by. the numeral 106. The tool 106 is provided with the usual stem 108 having a head 110 under which the tongs of the grappling hooks 82 engage. Tool 106 may be a testing tool of the type disclosed in my prior United States Patents No. 2,731,827, issued January 4, 1956; 2,807,955, issued October 1, 1957; or 2,841,007, issued July 1, 1958. Such tools usually include spaced packers mounted on a body, one being shown at 107, and at least one fluid passageway through the tool and opening to the area between the packers. After the packers are expanded into sealing engagement with the interior wall of the stand to form spaced barriers therein, fluid under pressure is applied through the passageway and discharged externally of the tool to the annular space between the packers at a predetermined pressure in order to test the stand and the coupling joint for leaks.

While the invention is being described in connection with a testing tool for oil or gas well flow tubing, it is appreciated that any tool inser-table into well tubing and used for supplying a fluid to the well to treat the same may be employed.

In the particular environment shown, the test tool 106 is provided with a reduced neck 11 1 which can fit up into the bore 32. The neck 11 1 is provided with an annular groove 1 12, and O-rings 114 provided on either side of the groove 112 seal off the same. The tool 106 is provided with at least one fluid passageway 116 which opens in a port 118 within the groove 112. Body portion 26 is provided with a lateral passageway 120 which opens in the bore 32 at a position between the barriers formed by the O-rings 114. A conduit 1 24 is connected to the passageway 120 and extends to a suitable source of fluid pressure 126. When the tool 106 has been moved by the grappling means 70 to the position shown in FIGURE 3, fluid under pressure is flowed from the source 126 through the conduit or line 124 to the tool, and the packers 108 are expanded to form spaced barriers in the stand, and then the fluid is applied to the areas between the spaced barriers to test the stand for leaks.

The operation of the apparatus of the present invention may be described briefly as follows. The derrick man is stationed on the platform 22, and, when it is desired to add another stand to the string of well tubing, the derrick man swings the elevator 20 over to a position beside the derrick and latches the same onto the upper end of a racked stand. At the time the derrick man latches the elevator onto the stand S, the automatic connect and disconnect apparatus 10 is placed over the top of the stand as shown in FIGURE 3. The stand S with the automatic connect and disconnect apparatus is then elevated by the driller and swung back int-o axial alignment to a previously-run stand. which has been lowered into the well with its upper end positioned immediately above the usual holding slips. With the stand S in a position aligned with the previously-run stand, the automatic connect and disconnect apparatus 10, as well as the point where the elevators 20 are attached to the stand, are at a position out of reach of the derrick man on the platform 22. However, the stand S can be threaded onto the previouslyrun stand, as the thrust bearing 34 interposed between the body portion 26 and the end of the stand permit the stand to be rotated without rotating the automatic connect and disconnect apparatus 10 and its various fluid pressure conduits. When the stand S is in its elevated position, the grappling means 70 is supported within the cylinder 48 and its hoisting cable, including its flexible weights 92, is deviated past the traveling block 18.

After the stand S has been coupled to the previouslyrun stand, and prior to the testing of the stand, the testing operator, who may be either at the floor level or on the platform 22 depending on where the hoisting drum 102 and the sources of fluid pressure 61 and 126 are located, then operates the hoisting drum 102 to lower the grappling hooks 82 downwardly through the body portion 26 and the stand S into the previously-run stand until the hooks 82 pass over the head of the test tool 108 which is suspended in the previously-run stand. The grappling means 70 is then raised so as to slide the testing tool 106 upwardly through the stand to be tested until the neck 1 10 of the testing tool is in the position shown in FIGURE 3 'within the bore 32. When the testing tool 106 is in this position, the testing operator can then apply fluid under pressure from the source 126 through the conduit 124 into the testing tool to reset the packers 108, if the same are set by fluid pressure, and then to apply fluid to the space between the barriers set up by the packers.

Once the testing operation has been completed, and it is determined that the stand S has a satisfactory coupling joint to the previously-run stand and is leakproof, the testing operator then applies fluid pressure from the source 61 through the conduit 60 into the cylinder 43. This causes the piston 52 to be extended into the cylinder and the ring nut 64, traveling with the piston, has is camming surface 67 engage the leaf springs 84 to compress the same inwardly. This causes the hooks 82 to be released from the head 110, and the connect and disconnect apparatus 24 then can be elevated off the end of the stand by further raising the grapple, and the stand along with the rest of the string can be lowered into the well. The procedure is then repeated with additional stands being attached and tested in sequence.

While the apparatus described above fully accomplishes the objects and advantages of the present invention, it is, of course, within the scope of the present invention that certain changes and modifications may be made without departing from the spirit of the invention. Therefore,

the terminology used in this specification is for the purpose of description and not for limitation, as the scope of the invent-ionis defined in the claims. i

What is claimed is: a

1. An automatic connect and disconnect apparatus for use in raising and loweringa tool within a stand of well tubing, wherein said tool includes a head portion which may be engaged by a grappling means andwherein means are provided for raising and lowering the grappling means Within the said automatic connect and disconnect apparatus said apparatus comprising: a

a body portion having a bore therethrough,

an annular sleeve extending downwardly from said stand can be rotated while the body portion and sleeve are stationary; V open-ended cylinder means connected to the upper end of said body portion, said cylinder means having a I longitudinal bore therethrough in axial alignment with the bore of said body portion;

a tubular piston movable in said boreiof said cylinder,

a grappling means including grappling hooks disposed within the bore of said body portion means formoving said grappling means longitudinally'within the bores of said body portion and said cylinder, 7

spring means associated with said grappling means for normally urging said grappling hooks toward a contracted grappling position, I a

cam means carried by said tubular piston'for engaging said spring means to positively expand said grappling hooks only when said tubular piston is moved downwardly within said cylinder and when said grappling means is positioned within said cylinder, 7

means normallyrurging said tubular piston to an upper retracted position within said cylinder, and

fluid pressure means connected to said cylinder for urging said tubular piston downwardly to cause said cam means to engage said spring means and to thereby release said grappling hooks from a grappling position. 7 a

2. In combination with a testing tool insertable in well tubing and having at least one conduit therein with an inlet for receiving atest fiuid,

an automatic connect and disconnect apparatus sup-l ported on the end of said well tubing for use in raising and lowering said tool within the well tubing, said apparatus comprising: a

a a; body portion having a-b ore therethrough-for receiving said tool, i a an annular sleeveextending downwardly from said body 7 portion and adapted to fit over theend of said well tubing, 7 conduit means connected to said body portion for supplying testingfluidithrough the inlet to the conduit injs'aidtool, p r open-endedcylinder'means connected to' the upper end of said body portion, said cylinder'means having a longitudinal bore therethrough in axial alignment withthe bore ,of said body portion, a tubular piston movable-in said bore of said cylinder, a grapplingmeans"including grappling hooks disposed within the bore of s'aid'bodygportion and meansfor moving said grappling means longitudinally within 1 the bores of said body portion and said cylinder, spring means associated with said grappling means for normally urging said grappling hookstoward a contracted grappling position, 7 cam means'carried by said tubular piston for engaging said spring means to positively expand said grappling I hooks only when' said tubular piston is moved downwardly'within said cylinder and when said grappling means is'positoned withinsaid cylinder, means'normally urging said tubular piston to an upper retracted position within said cylinder, and fluid pressure means connected to said cylinder for urg ing said tubular piston downwardlyto cause said cam means to engage said spring means' and to thereby release said grappling hooks from a grappling position.

References Cited bytlre Examiner V .UNITED STATES-PATENTS 1,540,195 6/25 Thrift 166-70'X 1,719,144 V 7/29 Stokes etal. 294-862 2,505,088 4/50 Athy 254- 2,507,127 7 5/50 True 294-8617 2,595,902 5/52 Stone 166-77.5 2,610,691, 9/52 Berry 166-4 2,630,179 3/53 Brown 166-70 X 2,652,717 9/53 Bush et al. 166-4 X 2,678,190 5/54 Crake 254-145 2,953,919v 9/60 Potts 73-405 X 2,982,125 5/61 Gilreath 166-4 X 3,048,998 8/62 Gilreath 73-405 "3,061,011' 10/62 Paget 166-77.5 3,076,509 2/63 Burns et a1 166-70 CHARLES E. OCONNELL, Primary Examiner. BENJAMIN HERSH, Examiner, V 

1. AN AUTOMATIC CONNECT AND DISCONNECT APPARATUS FOR USE IN RAISING AND LOWERING A TOOL WITHIN A STAND OF WELL TUBING, WHEREIN SAID TOOL INCLUDES A HEAD PORTION WHICH MAY BE ENGAGED BY A GRAPPLING MEANS AND WHEREIN MEANS ARE PROVIDED FOR RAISING AND LOWERING THE GRAPPLING MEANS WITHIN THE SAID AUTOMATIC CONNECT AND DISCONNECT APPARATUS AND APPARATUS COMPRISING: A BODY PORTION HAVING A BORE THERETHROUGH, AN ANNULAR SLEEVE EXTENDING DOWNWARDLY FROM SAID BODY PORTION AND ADAPTED TO FIT OVER AN END OF THE STAND OF TUBING; A ROTATABLE BEARING MEANS CARRIED BY SAID BODY PORTION AND SAID SLEEVE, SAID ROTATABLE BEARING MEANS POSITIONED WITHIN SAID BODY PORTION AND SAID SLEEVE TO ENGAGE THE END OF THE STAND OF TUBING WHEREBY THE STAND CAN BE ROTATED WHILE THE BODY PORTION AND SLEEVE ARE STATIONARY; OPEN-ENDED CYLINDER MEANS CONNECTED TO THE UPPER END OF SAID BODY PORTION, SAID CYLINDER MEANS HAVING A LONGITUDINAL BORE THERETHROUGH IN AXIAL ALIGNMENT WITH THE BORE OF SAID BODY PORTION; A TUBULAR PISTON MOVABLE IN SAID BORE OF SAID CYLINDER, A GRAPPLING MEANS INCLUDING GRAPPLING HOOKS DISPOSED WITHIN THE BORE OF SAID BODY PORTION MEANS FOR MOVING SAID GRAPPLING MEANS LONGITUDINALLY WITHIN THE BORES OF SAID BODY PORTION AND SAID CYLINDER, SPRING MEANS ASSOCIATED WITH SAID GRAPPLING MEANS FOR NORMALLY URGING SAID GRAPPLING HOOKS TOWARD A CONTRACTED GRAPPLING POSITION, CAM MEANS CARRIED BY SAID TUBULAR PISTON FOR ENGAGING SAID SPRING MEANS TO POSITIVELY EXPAND SAID GRAPPLING HOOK ONLY WHEN SAID TUBULAR PISTON IS MOVED DOWNWARDLY WITHIN SAID CYLINDER AND WHEN SAID GRAPPLING MEANS IS POSITIONED WITHIN SAID CYLINDER, MEANS NORMALLY URGING SAID TUBULAR PISTON TO AN UPPER RETRACTED POSITION WITHIN SAID CYLINDER, AND FLUID PRESSURE MEANS CONNECTED TO SAID CYLINDER FOR URGING SAID TUBULAR POSTON DOWNWARDLY TO CAUSE SAID CAM MEANS TO ENGAGE SAID SPRING MEANS AND TO THEREBY RELEASE SAID GRAPPLING HOOKS FROM A GRAPPLING POSITION. 